WP Super Cache ??

Need help with WP Super Cache configuration.

Installed WP Super Cache, site only runs in ‘Half On’ (with most browsers) but pages not cached.

With WP Super Cache Status ‘On’ my site is only visible with Safari but pages not cached.

Could someone check my configuration please, site is very slow.

My Site: https://www.oorlogsslachtoffers.nl/deurne

/Root .htaccess

# BEGIN WPSuperCache
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /deurne/
AddDefaultCharset UTF-8
RewriteCond %{REQUEST_URI} !^.*[^/]$
RewriteCond %{REQUEST_URI} !^.*//.*$
RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress|wp-postpass_).*$
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{DOCUMENT_ROOT}/deurne/wp-content/cache/supercache/%{HTTP_HOST}/deurne/$1/index.html.gz -f
RewriteRule ^(.*) /deurne/wp-content/cache/supercache/%{HTTP_HOST}/deurne/$1/index.html.gz [L]

RewriteCond %{REQUEST_URI} !^.*[^/]$
RewriteCond %{REQUEST_URI} !^.*//.*$
RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress|wp-postpass_).*$
RewriteCond %{DOCUMENT_ROOT}/deurne/wp-content/cache/supercache/%{HTTP_HOST}/deurne/$1/index.html -f
RewriteRule ^(.*) /deurne/wp-content/cache/supercache/%{HTTP_HOST}/deurne/$1/index.html [L]
</IfModule>
# END WPSuperCache

# BEGIN supercache
<IfModule mod_mime.c>
  AddEncoding gzip .gz
  AddType text/html .gz
</IfModule>
<IfModule mod_deflate.c>
  SetEnvIfNoCase Request_URI \.gz$ no-gzip
</IfModule>
<IfModule mod_headers.c>
  Header set Cache-Control 'max-age=300, must-revalidate'
</IfModule>
<IfModule mod_expires.c>
  ExpiresActive On
  ExpiresByType text/html A300
</IfModule>
# END supercache

<FilesMatch "\.(ico|pdf|flv|jpg|jpeg|png|gif|js|css|swf)$">
Header set Expires "Thu, 15 Apr 2010 20:00:00 GMT"
</FilesMatch>

# BEGIN ETag
 FileETag None
# END ETag

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /deurne/

RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP_COOKIE} !^.*(comment_author_|wordpress|wp-postpass_).*$
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html.gz -f
RewriteRule ^(.*) /wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html.gz [L]

RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{QUERY_STRING} !.*attachment_id=.*
RewriteCond %{HTTP_COOKIE} !^.*(comment_author_|wordpress|wp-postpass_).*$
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html -f
RewriteRule ^(.*) /wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html [L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /deurne/index.php [L]
</IfModule>
# END WordPress

/Cache .htaccess

# BEGIN supercache
<IfModule mod_mime.c>
  AddEncoding gzip .gz
  AddType text/html .gz
</IfModule>
<IfModule mod_deflate.c>
  SetEnvIfNoCase Request_URI \.gz$ no-gzip
</IfModule>
<IfModule mod_headers.c>
  Header set Cache-Control 'max-age=300, must-revalidate'
</IfModule>
<IfModule mod_expires.c>
  ExpiresActive On
  ExpiresByType text/html A300
</IfModule>
# END supercache

advanced-cache.php

<?php
# WP SUPER CACHE 0.8.9.1
function wpcache_broken_message() {
	if ( false == strpos( $_SERVER[ 'REQUEST_URI' ], 'wp-admin' ) )
		echo "<!-- WP Super Cache is installed but broken. The path to wp-cache-phase1.php in wp-content/advanced-cache.php must be fixed! -->";
}

if ( !include_once( '/home/osd/domains/oorlogsslachtoffers.nl/public_html/deurne/wp-content/plugins/wp-super-cache/' . 'wp-cache-phase1.php' ) ) {
	if ( !@is_file( '/home/osd/domains/oorlogsslachtoffers.nl/public_html/deurne/wp-content/plugins/wp-super-cache/' . 'wp-cache-phase1.php' ) )
		register_shutdown_function( 'wpcache_broken_message' );
}
?>